What ELSE could cause steering vibration?

[avacado11]

2006 BMW 330XI 96k miles.

I've been having this vibration issue ever since I got it at 90k. problem is the steering wheel will vibrate at 70-80mph(sometimes 65 mph). This usually indicates a balance issue, in which I have had the wheels balanced 3 times already by my mechanic, issue still exists(it's not his machine because my other cars drive fine).

nearly every time I hit a bump or imperfection on the highway(65-80mph) the steering wheel will begin to vibrate even more. It usually settles down after a mile or if I give it heavy gas, but will come back if I let off on the pedal..

The rims are NOT bent. Originally the passenger side CV joint had some side to side play in it, so I had both sides replaced with new ones(the whole axle). Front struts replaced too along with sway bar end links. Everything else looks good and the front end is tight, no play in anything.

I'm still baffled with this situation. Could it possibly require a completely new front end? Could the steering rack be damaged?

The only thing I have not yet done is an alignment and replaced the tires. The tires are cheap Milestar MS932s that were brought new from DTD 5 months ago. My mechanic did point out that 2 of them had excessive run out(he could see it while it was spinning on the balancer, he mounted them on the rear). The other 2 were ok.

Is there anything else I could look at before I chuck the tires for something high end?

 

[mclasser]

Thoroughly inspect the suspension, since going over bumps exacerbates the issue.

BMW's usually have more complex bushing setups so you want to check each one. It's possible jacking up one end will load up a bushing/ball joint so also jacking under the LCA to neutralize it may be needed.

 

[Merkava_4]

Internal tread separation is what you got. Doesn't show up until the car's weight is on the tire.

 

[avacado11]

Originally Posted By: Merkava_4
Internal tread separation is what you got. Doesn't show up until the car's weight is on the tire.


Man that sucks!

I was hoping these to be atleast half decent tires. They still have a ton of tread left 9/32nds and they aren't showing any abnormal wear. Could it seriously be tread separation? I mean they don't vibrate at 60 mph or anything over 85.

I already had the bushings checked through by my mechanic(who's worked on a handful of BMWs). Everything looks good on the front end.

 

[Rolla07]

So im not trying to be rude here but you bought a BMW (2006, yes I know) and you put cheap tires on it?! 2 having excessive run out is already a sign, id sell those tires and buy half decent new ones..cooper or wtv and hope that Merkava is right.

 

[goodtimes]

If the vibration didn't stop by putting almost new tires on the front and putting the worn front ones on the rear, it probably isn't the tires. Maybe it is the rotors. The high carbon rotors may stay true better.

 

[mehullica]

Have a Hunter Road Force Balance done on all the tires & see what the machine says.

 

[Nick1994]

Rotate the tires and see if the vibration changes.

I believe those BMWs are really picky with lower control arm bushings.

 

[Johnny2Bad]

If it's consistent at a specific road speed, it really points to tires and wheels. Something is not right there.

I've had tire/wheel combinations that vibrated at a specific speed (55 mph in my case) that were balanced properly according to the machine. The specific reason was never discovered, but swapping the wheels front to back solved it.

 

[Lyman]

We had a car where I work do this. It took over a year to figure out that the rack was bad on it. Drove perfect after it was replaced.

 

[The Critic]

On the E90 vehicles and especially ones of your vintage/mileage, check the tension strut bushings. You will need remove the fender liner to get a good view of the bushings, but generally a torn bushings on the tension strut assembly will cause the symptoms you are describing.

 

[Silverado12]

The shaking while going over bumps is a (almost) sure indication that something like a ball joint is bad on the front end. Take it to an alignment shop. They check all these parts before doing the alignment.

 

[tomcat27]

The symptom you describe: vibration after hitting a bump, indicate too much play in one or more of the front end steering and suspension components - period. if two of your tires have too much measured runout, no amount of switching or balancing will fix that. get good tires. I bought a car from Carmax that had 4 new tires on it. the tires were a brand I have never heard of (Epic). My shop spent a lot of time trying to make them right. no dice. bought new good tires, car was as smooth as silk.

 

[ARCOgraphite]

Likely a tire issue, though also easy to check rotor hat for runout on car - torqued. may have axle flange to rotor mating issue causing wobble that will have a resonance at certaing speed. if you have problem tires on both end of the same axle, periodically they will combine phase into a large node and really shake.

Now that ive said this, IDK if BMW uses a hat style rotors.

 

[artificialist]

This can often be caused by failed lower control arms.

That in mind, I wouldn't be surprised if the low price tires were the problem.

 

[avacado11]

Well...turns out it was the tires the WHOLE TIME. Would have been great if I found out it was the root of the problem...BEFORE I spent $1500 on the front end.

I bolted on a pair of rims with Cooper Zeon RS3-As on the front(same size as the Milestars on the rear). Thing rides perfect even at 110 MPH! I couldn't get past 65mph with the Milestars before all h*ll breaks loose(especially if I let off the gas).

Could have saved myself $1500 had I spent an extra $150 on tires. D*mn that's a lesson learned (-_-)

 

[sleddriver]

Originally Posted By: avacado11
Well...turns out it was the tires the WHOLE TIME. Would have been great if I found out it was the root of the problem...BEFORE I spent $1500 on the front end.
Just as I was fixing to type a response, I read your final post. Had to be cheap out-of-round tires or alignment or both. Just because a tire will balance doesn't mean it will roll smooth. A square wheel can be balanced but try driving on it!

Further, alignment is critical to a smooth front end and calm steering wheel at speed.

Godd to hear you figured it out.

 

[4WD]

Keep it a long time and the cost will be minimal - putting things in perspective- the extra work is 2 or 3 car payments for the average Joe (what is the lady version of average Joe, I should of included her) ... ?

 

[artificialist]

Originally Posted By: 4WD
Keep it a long time and the cost will be minimal - putting things in perspective- the extra work is 2 or 3 car payments for the average Joe (what is the lady version of average Joe, I should of included her) ... ?
Some people call an anonymous woman "Jane Doe."

 

[zrxkawboy]

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